In recent years, overdose from both licit and illicit drugs has been an increasingly common cause of death in persons fifteen to seventy years of age. After a suspected drug death, a major objective at autopsy is to determine whether any drugs measured in the decedent have played a role in the cause of death. Currently, post-mortem forensic drug analyses rely upon traditional biological matrices such as blood, urine, bile, and liver tissue. The specific matrix used for specimen retrieval depends, in part, on the time after death that the sample is collected and the consistency of collection, which may vary due to differences in clotting time, fluid movement and changes in cellular components. Once death has taken place, many drugs are released from their binding sites in tissue as pH decreases and the process of autolysis proceeds. By the time a sample has reached the clinical chemistry laboratory for analysis, it may be unsuitable for analysis. For example, drug concentrations in blood taken from an individual at one site may be twice the concentration as that taken at the same time from a different site (e.g., sublingual region versus femoral vein). In addition, in decaying cadavers, viable sample matrices typically are hard to retrieve and oftentimes are limited solely to putrefactive fluid in pleural cavities and blisters. Sample collection from blood, urine and body tissues also requires the use of protective gear to prevent possible spread of infection. Further, sample analyses typically are time-consuming, as various instrumentalities usually are employed for both qualitative and quantitative analyses of the samples.
There exists a need, therefore, for a fast, sensitive, and less invasive method to conduct forensic toxicology in post-mortem subjects than what is currently available.